Plasmonic Aluminum Nanohole Arrays as Transparent Conducting Electrodes for Organic Ultraviolet Photodetectors with Bias-Dependent Photoresponse

Abstract

Electrodes consisting of plasmonic Al nanohole arrays (Al-NHAs) were incorporated into organic ultraviolet (UV) photodetectors that exhibited bias-dependent photoresponse. Al-NHAs were designed by using three-dimensional finite-difference time-domain (3D-FDTD) simulations to produce strong UV absorbance in the active layer and enhanced internal electric field intensity. The nanosphere lithography fabricated Al-NHAs were incorporated into organic conventional devices, which produced two narrow response peaks under reverse bias and one broad response peak under forward bias, while ITO-based control devices can only produce twopeak photoresponse spectra. The bias-dependent photoresponse switching achieved by the Al-NHA-based devices is attributed to the plasmonic-enhanced internal electric field, which acts as a small forward bias and increases the driving force for hole diffusion. Conventional devices with planar Al electrodes and hole-only devices with both planar Al and an Al-NHA electrodes were also fabricated and evaluated to confirm the photoresponse mechanism. Plasmonic Al-NHA electrodes provide an approach for making ITO-free, flexible organic UV photodetectors with improved photoresponse and bias-dependent response tunability.

Aluminum Plasmonics Enriched Ultraviolet GaN Photodetector with Ultrahigh Responsivity, Detectivity, and Broad Bandwidth

“…[37] In addition to a 355 nm laser, our photodetector can be used for other UV frequencies because LSPR validates a broad spectral coverage. [38] For example, we evaluated this plasmon-empowered UV photodetector using a 325 nm laser. The maximum R and D* were 307 A W −1 and 7 × 10 12 cm Hz 1/2 W −1 , respectively, as shown in Figure S5 in the Supporting Information.…”

Highly stabilized flexible transparent capacitive photodetector based on silver nanowire/graphene hybrid electrodes

“…In this regard, various flexible and conductive electrodes for photodetectors have been studied, such as carbon nanotubes (CNTs) 3 , graphene 4 – 8 , metal nanowires 9 , 10 , metal nanogrids 11 , 12 , and thin films 13 . Among these alternatives, one-dimensional (1D) metal networks, such as metal nanowires and metal fiber electrodes, have been extensively studied.…”

Highly Stabilized Flexible Transparent Capacitive Photodetector Based on Silver Nanowire/Graphene Hybrid Electrodes

“…In this regard, various exible and conductive electrodes for photodetectors have been studied, such as carbon nanotubes (CNTs) 3 , graphene [4][5][6][7][8] , metal nanowires 9,10 , metal nanogrids 11,12 , and thin lms 13 . Among these alternatives, one-dimensional (1D) metal networks, such as metal nanowires and metal ber electrodes, have been extensively studied.…”